High speed steels have heretofore been frequently used for production of metal-cutting tools, metal molds, metal processing dies, and the like. As hard alloy materials having a hardness higher than high speed steels, there have been broadly been used cemented carbide alloys, especially materials composed of tungsten carbide or a double carbide of tungsten with titanium, tantalum, niobium, etc., and cobalt as a binding material.
Since such cemented carbide comprises tungsten as the main element, its specific gravity is as high as 13 to 15, and further, the cost of the raw material is high. Moreover, tungsten resources are now decreasing. Accordingly, the development of substitute materials is of great technical significance.
There are hardly present tool materials having properties intermediate between properties of high speed steel and cemented carbide, and development of tool materials having such specific properties has been highly demanded in the art.
It is a primary object of this invention to solve the foregoing problems. More specifically, the primary object of this invention is to provide a novel hard alloy having a hardness higher than that of high speed steel and such hardness and strength as to make it comparable to cemented carbides. Moreover, the alloy of the present invention has a low specific weight and can be manufactured at a low cost without the fear of shortage of the raw materials involved. The present invention also provides a method of making such hard alloy.